code: def test_marre(self):
      assert (
          round(
              abs(
                  metrics.marre(self.series1, self.series2)
                  - metrics.marre(
                      self.series1 + 100, self.series2 + 100
                  )
              ),
              7,
          )
          == 0
      )
      self.helper_test_multivariate_duplication_equality(metrics.marre)
      self.helper_test_multiple_ts_duplication_equality(metrics.marre)
      self.helper_test_nan(metrics.marre)
  
imports: import numpy
  import pandas
  import pytest
  from darts import TimeSeries
  from darts.metrics import metrics
label_desc: Use image node_id 9 for calling the TestMetrics obj's underlying member method code with example usage: obj.test_marre() without return types